The present invention relates to connectors for holding together large shipping containers. These containers are used for transporting various cargo items primarily by ship and/or truck. The containers are approximately eight feet high and eight feet wide with a standard length of twenty feet. However, containers with shorter than twenty foot lengths are available in, for example, ten foot and five foot lengths and are appropriately called half and quarter length containers respectively.
Shipping containers enjoy a minimum cost per cubic foot if the container is the standard twenty foot INTERNATIONAL ORGANIZATION FOR STANDARDS (ISO) length since ship and truck handling and storage equipment are designed to handle the "standard" twenty foot length. Therefore, it is desirable to join non-standard length containers to form a single unit of twenty foot length.
Container connectors have been utilized to fasten and hold together containers and have taken on many forms. One such device that has been utilized in the past is found in U.S. Pat. No. 3,389,663 to Gutridge which utilizes a collection of non-standard parts and includes two mechanically activated non-independent heads for connecting containers. A somewhat similar device is found in U.S. Pat. No. 3,752,511 to Racy and a highly complex version is found in U.S. Pat. No. 3,556,456 to Lunde. Yet all of these devices fail to provide an inexpensive, simple, safe to operate device with independently operable and adjustable locking heads that can be operated with standard hand tools.